What do the tools in options panel( like Tag Bevel )in edit mode do?
The options in the Options Panel for tagging edges are the same as the edges menu with only a slight difference that I can see. Most notably in Bevel and Crease, in that the weight added is always at 1. 


Crease marks edges for use with subsurf, with a weight of 1
Bevel marks edges for use with Bevel modifier, with a weight of 1
Sharp will mark edges sharp for edge split modifier
Seam will mark seams for UV unwrap
Freestyle Edge Mark will mark edges for use with Freestyle


To use the Tag Bevel, Tag Crease , Tag Sharp, Tag Seam tool, it is as simple as selecting each edge with Ctrl + RMB